What kind of sensors? I doubt the temperature sensors would fail on take-off because it ain't going fast enough to generate the heat (unless there's a fire).
Thermocouple circuits for obvious reasons are designed for an off-scale reading when they are destroyed or disconnected, that didn't happen during the entire mission until the re-entry, that we know of.
If you mean another another type of sensor that can detect tile damage, I would be interested to know about that, otherwise the debris smashing into the port wing is what I would be looking at closely as well as every other possibility.
So call me a tin-foiler if you like.